Gaming machines, such as slot machines, video poker machines and the like, have been a cornerstone of the gaming industry for several years. Generally, the popularity of such machines with players is dependent on the likelihood (or perceived likelihood) of winning money at the machine and the intrinsic entertainment value of the machine relative to other available gaming options. Where the available gaming options include a number of competing machines and the expectation of winning each machine is roughly the same (or believed to be the same), players are most likely to be attracted to the most entertaining and exciting of the machines. Shrewd operators consequently strive to employ the most entertaining and exciting machines available because such machines attract frequent play and hence increase profitability to the operator. Accordingly, in the competitive gaming machine industry, there is a continuing need for gaming machine manufacturers to produce new types of games, or enhancements to existing games, which will attract frequent play by enhancing the entertainment value and excitement associated with the game.
One concept that has been employed to increase the entertainment value of a slot machine is a “wild” symbol that substitutes for other basic reel symbols. Often times the wild symbol will randomly appear on a selected pay line along with a series of other matching symbols to complete a win. The addition of a wild symbol or symbols to the plurality of basic reel symbols may increase the perceived chances of a win and enhance the entertainment value of the machine. Wild symbols have existed as a standard gaming feature for many years and frequent players of slot machines view wild symbols as routine.